Charon, version $Name: REL_1_5 $

... keeping your business models and your EJB-implementations synchronized.

Description

Charon is generator to produce PowerTier .per files from TogetherJ class-diagrams and vice versa.

One of the key features of TogetherJ is its excellent support for roundtrip engineering. This means, that class-diagrams and their corresponding Java source code files are allways kept synchronized. With Enterprise JavaBeans (EJBs), however, this quickly makes class-diagrams unreadable because they contain all the EJB implementation details. It is much better to have class-diagrams with just one class per EJB.

PowerTier can generate Entity Beans from specifications made in its Builder tool. The PowerTier Builder is a non-diagram-style editor which stores everything in a .per file. This file is used by PowerTier's ps-gen to generate Entity Beans. This saves a lot of handcrafting.

Charon links TogetherJ and PowerTier by generating PowerTier .per files from TogetherJ class-diagrams and by updating class-diagrams from .per files. Charon preserves the rondtrip engineering capabilities and simplifies the class-diagrams by requiring only one class per EJB.

Charon provides the following properties for the .per file generation, which can be entered in the TogetherJ inspector:

Diagram level

property	description	default
Project	the name of the project at the first line of the .per file	the name of the TogetherJ project file
ProjDomainName	an entry in the PersistencePreferences block of the .per file	package name for this diagram
ProjDomainRootFileName	an entry in the PersistencePreferences block of the .per file	package name for this diagram
ProjDomainOutputDir	an entry in the PersistencePreferences block of the .per file	.\ejb
ProjRootFileName	an entry in the PersistencePreferences block of the .per file	package name for this diagram
ProjInSubDir	an entry in the PersistencePreferences block of the .per file	False
ProjPackage	an entry in the PersistencePreferences block of the .per file	package name for this diagram
ClassPostfix	this string will be appended to all class names in the .per file	empty string

Class level

property	description	default
persistent	flag for marking for export	false
TableName	an entry in the PersistentClass block, if specified	not specified (will not be generated)
ExistingTable	an entry in the PersistentClass block	false (will not be generated)
ReadOnly	an entry in the PersistentClass block	false (will not be generated)
DistributionOption	an entry in the PersistentClass block	AllReadWrite

Attribute level

property	description	default
key	true, if this attribute is part of the key	False
type	PowerTier type for this attribute	the default value depends on the java type, as described in the next table
ColumnName	a different name for the column in the database table for this attribute	not specified (will not be generated)
OptimisticControl	an entry in the PersistentClass block	false (will not be generated)
length	length for the PowerTier type `char`	80
scale	scale for the PowerTier type `decimal` (not implemented yet)	0
NullAllowed	an entry in the PersistentClass block	false (will not be generated)

Default Mapping from Java types to PowerTier types

Java type	PowerTier type
int	int
String	char
Date	time
BigDecimal	decimal
float	float

Relationship

property	description	default
persistent	flag for marking for export	false
clientDeleteAction	an entry in the Relationship block	removeRelationPointer
supplierDeleteAction	an entry in the Relationship block	removeRelationPointer
in the `Link` tab of the inspector: client role	client role	name of the client class, first character lowercased
in the `Link` tab of the inspector: client cardinality	client cardinality	0..1
in the `Link` tab of the inspector: supplier role	supplier role	name of the supplier class, first character lowercased
in the `Link` tab of the inspector: supplier cardinality	supplier cardinality	0..1

The final version will be able to create new class-diagrams from .per files or update them if they exist already.

Pre-Requisites

TogetherJ version 3.0 or later
PowerTier version 6.0 or later

Installation

Unzip the file CHARON.zip into c:\Together\Modules (c:\Together is the path to your local TogetherJ-Installation).
Copy the file c:\Together\Modules\charon\charon.config into c:\Together\config.

Using Charon

Instrument your class-diagram
- mark the persistent classes and associations (persistent = true)
- specify length and scale for attributes with String and BigDecimal types (default for length for String: 80)
- specify optionally table names and column names
- specify values for other PowerTier properties
Convert a class-diagram into a .per file
- Select the tab Modules, right-click on Charon and press run
- Charon generates the .per file in the same directory where the TogetherJ project file is and names it with the name of the processed diagram

Now you can generate the EJBs using PowerTier's ps-gen and edit the EJBs' source code.

To create new class-diagrams from .per files or to update existing class-diagrams ...

(will be added soon)

Known Limitations and Defects

Generation from .per to TogetherJ is not yet implemented
scale will not be evaluated for the PowerTier type decimal

Authors

Coding and documentation: Frank Buß (fb@frank-buss.de)
Documentation and quality assurance: Thomas Heinrich (ThomasHeinrich@swol.de)

License

Charon is freely available under the GNU General Public License.

Trademarks

PowerTier is a trademark of Persistence Software, Inc.
TogetherJ is a trademark of Togethersoft, Inc.